The present disclosure relates to an electrolytic solution containing a solvent and an electrolyte salt and a battery using the electrolytic solution.
In recent years, portable electronic devices such as combination cameras (videotape recorder), mobile phones, and notebook personal computers have been widely used, and it is strongly demanded to reduce their size and weight and to achieve their long life. Accordingly, as a power source for the portable electronic devices, a battery, in particular a light-weight secondary batter capable of providing a high energy density has been developed.
Specially, a secondary battery using insertion and extraction of lithium for charge and discharge reaction (so-called lithium ion secondary battery) or a secondary battery using precipitation and dissolution of lithium (so-called lithium metal secondary battery) is extremely prospective, since such a lithium ion secondary battery or such a lithium metal secondary battery can provide a higher energy density compared to a lead battery and a nickel cadmium battery.
In such a secondary battery, an electrolytic solution in which an electrolyte salt such as lithium hexafluorophosphate is dissolved in an ester carbonate solvent such as propylene carbonate and diethyl carbonate is widely used (for example, refer to Japanese Patent No. 3294400). In particular, for improving the load characteristics, the storage characteristics, the electrochemical characteristics and the like, an electrolytic solution containing, for example, an anhydride composed of sulfonic acid and carboxylic acid, sulfate having a trialkylsilyl group, sulfonate or the like is also used (for example, refer to Japanese Unexamined Patent Application Publication Nos. 2002-008718 and 2002-359001).
In the recent electronic devices, there is a tendency that the calorific value is more and more increased due to factors such as high performance of electronic parts typified by a CPU (central processing unit). Thus, the secondary battery is exposed in the high temperature atmosphere, and thereby the storage characteristics tend to be lowered. Furthermore, there is a tendency that the high performance and the multi-functions of the electronic devices are increasingly developed. Thus, there is a tendency that the discharge capacity is easily lowered by frequently repeating charge and discharge of the secondary battery. Therefore, it is aspired that the storage characteristics and the cycle characteristics of the secondary battery could be further improved.
Therefore, it is desirable to provide an electrolytic solution and a battery capable of improving the storage characteristics and the cycle characteristics.